textproduct: Quad Cities

KEY MESSAGES

- After a cooler than normal second half of the week, rain chances will be on the increase just before the weekend.

- A pattern change over the weekend will bring warmer than normal temperatures to the area next week.

SHORT TERM /THROUGH WEDNESDAY/

Issued at 159 PM CDT Tue May 19 2026

Slowly clearing skies will be seen tonight into Wednesday with cooler than normal temperatures.

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/

Issued at 159 PM CDT Tue May 19 2026

Thursday through Friday night Assessment...high (>80%) confidence of a storm system. Low to medium (20-40%) confidence on rainfall.

The second half of the work week will be characterized by cooler than normal temperatures.

The global models have a storm system forecast to impact the Midwest late in the week but there are timing differences. Interestingly, most ensemble members of the global models take the main surface low east of the Mississippi which raises questions regarding the overall rainfall potential for the area.

The timing differences between the various models and their ensembles result in an overall risk for rain that potentially could start as early as Thursday or hold off until Friday. Based on the overall large scale picture, the various global models are indicating very late Thursday night into Friday as being the most likely time period for any rain to occur. Here the model consensus has a 60-70% chance of rain. Rain would then linger into Friday evening before ending.

Overall rainfall amounts will be variable; Some locations will see under 0.25 inches of rain while some may see close to an inch.

Sunday through Tuesday Assessment...a certainty (>95%) of warmer than normal temperatures

The holiday weekend will be mainly dry although a rogue diurnal shower or thunderstorm cannot be ruled out.

Starting Sunday the pattern change will be noticeable as temperatures trend above normal and are then expected to remain above normal next week.

All models show an upper level ridge building along the east coast which will place the Midwest in southwest flow aloft. Humidity levels will be on the increase with dew points raising initially into the upper 50s and lower 60s; tolerable for all but the most sensitive people.

Starting Tuesday humidity levels will be much more noticeable and uncomfortable as dew points climb into the mid 60s. The increased moisture combined with the very warm temperatures and a passing upper level disturbance is expected to result in mainly diurnal convection Tuesday afternoon and evening. Right now the model consensus has rain chances at 15 to 25 percent.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1212 PM CDT Tue May 19 2026

Cold front is east of the Mississippi with MVFR CIGS all across Iowa. Wind gusts up to 27 knots will create considerable low level mechanical turbulence through sunset. Very short term models have CIGS raising to VFR too quickly and the 18z TAFs delay the arrival of VFR until after 00z/20. After 00z/20 wind will diminish to around 10 knots and become more northerly as high pressure builds into the Midwest.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.